Sensor system, including a plurality of individual and separate sensor elements

ABSTRACT

A sensor system including a plurality of individual and separate sensor elements. Each of the individual sensor elements is independently functional. The individual sensor elements of the sensor system being formed in one piece from parts of a wafer or a vertically integrated wafer stack. The sensor system including at least one separation structure, in particular a scribe line, between the individual and separate sensor elements.

CROSS REFERENCE

The present application claims the benefit under 35 U.S.C. § 119 ofGerman Patent Application No. DE 102020204773.1 filed on Apr. 15, 2020,which is expressly incorporated herein by reference in its entirety.

FIELD

The present invention is directed to a sensor system including aplurality of individual and separate sensor elements.

BACKGROUND INFORMATION

Sensor systems, in particular micromechanical sensor systems, aregenerally available; micromechanical sensors for measuring, for example,acceleration, rotation rate, pressure, and other physical variables arethus manufactured in mass production for various applications in theautomotive and consumer fields. One important trend in the refinement ofsensors is the improvement of the performance. In some applications,above all a significant reduction of the noise has great importance.Other applications require a massive reduction of offset or sensitivityerrors.

Performance improvements are fundamentally achievable by new developmentof improved sensors, for example by optimized MEMS elements, improvedevaluation circuits (ASICs), measures taken in the packaging, or alsoduring the calibration/testing of the sensors. However, very highdevelopment costs are required depending on the complexity of theimprovement measure, in particular if disruptive and not onlyincremental improvements of the performance are required.

For example, a lower-noise signal may be achieved by evaluating thesignals of multiple sensor elements, as is described, for example, inU.S. Patent Application Publication No. US 2006/0082463 A1; however, itis disadvantageous here that a relatively high expenditure is requiredfor the overall system integration and the installation size interdictsa use in size-sensitive applications or at least makes it much moredifficult.

Furthermore, methods of vertical integration are available, in which aMEMS wafer or a wafer including a micromechanical sensor structure isbonded on an ASIC wafer or a wafer including an associated evaluationcircuit or both are connected to one another, in particular the ASICwafer implementing both the electronic evaluation circuit and also thecap for the micromechanical sensor structure of the MEMS element, cf.,for example, German Patent Application No. DE 19 616 014 A1 or U.S.Patent Application Publication No. US 2006/0208326 A1.

SUMMARY

A sensor system according to an example embodiment of the presentinvention may have the advantage over the related art that by using aplurality of individual and separate sensor elements (or individualsensor elements) within the sensor system—i.e., in particular by usingan array (of at least 2×1, in general n×m) identical semiconductorcomponents, each individual semiconductor component being independentlyfunctional—the plurality of individual and separate sensor elements,i.e., the array, being formed in one piece from parts of a wafer (orsubstrate) or from parts of two wafers (or two substrates), it is notonly possible to achieve an improved signal quality (performance) of theentire sensor system, but also to reduce the development expenditure orto achieve flexibility in the development so that niche applications,for example having increased performance demands, for which a separateproduct development (due to high development costs at minor quantity)would not be cost-effective, are efficiently operable. It is thuspossible according to the present invention to implementhigh-performance sensors, which are scalable in a simple manner withrespect to performance, with low development costs and smallinstallation size at the same time.

Advantageous designs and refinements of the present invention may beinferred from the present disclosure, including the description hereinwith reference to the figures.

According to an example embodiment of the present invention, it is inparticular preferably provided that the individual and separate sensorelements of the sensor system—with the exception of the connection viathe substrate potential—are exclusively or at least essentially solelymechanically connected to one another, in particular are exclusivelymechanically connected or are only electrically connected to one anothervia a redistribution level situated on a side of the second substratefacing away from the first substrate (or also situated on a side of thefirst substrate facing away from the second substrate). Because theindividual and separate sensor elements are exclusively mechanically oressentially solely mechanically connected to one another, it isadvantageously possible according to the present invention to group orcombine the various sensor elements in different ways into sensorsystems (or into different types of arrays of sensor elements) (or—inthe case of a redistribution level—the effort for implementing differentsensor systems (or different arrays of sensor elements) is significantlyreduced, because only the redistribution level is to be adapted ifnecessary).

In particular, in accordance with an example embodiment of the presentinvention, it is furthermore provided that the individual and separatesensor elements include a vertically integrated wafer stack made up of afirst chip arrangement including the micromechanical sensor structureand the first substrate and a second chip arrangement including theassociated evaluation circuit and the second substrate. In this way, itis advantageously possible according to the present invention that botha cap of the micromechanical sensor structure is implemented by theevaluation circuit and at the same time the evaluation circuitassociated with a sensor structure is situated in spatial proximity, sothat different arrays of sensor elements and thus the flexibilityaccording to the present invention are possible during the developmentof new configurations (or types of arrays of individual sensor elements)of the sensor system. The implementation of vias, in particular in theform of TSV (through-silicon vias) advantageously enables the electricalconnection between the first and second substrate and/or between thefirst and second chip arrangement, so that either electrical signals ofthe micromechanical sensor structure (MEMS signals) or electricalsignals of the evaluation circuit (ASIC signals) may be led from theinside of the wafer stack to the outside of the stack. It is furthermorepreferred according to the present invention that the sensor systemaccording to the present invention including a plurality of individualand separate sensor elements is usable as a so-called chip scalepackage, i.e., the footprint of the sensor system is defined by the sizeof the plurality of individual and separate sensor elements and nofurther housing or secondary packaging of the sensor system takes place.The sensor system according to the present invention, i.e., an array ofindividual and separate sensor elements (or of equivalent individualsemiconductor components) may preferably—in particular as a chip scalepackage—be provided, for example, so it may be directly soldered on acircuit board or is vertically stackable via flip-chip mounting onanother chip or an interposer or a lead frame or a package substrate.Furthermore, it is preferred that each of the individual sensor elementsis independently functional and in particular the individual sensorelements of the sensor system are formed in one piece from parts of onewafer in each case with respect to their first and second chiparrangement and/or with respect to their first and second substrate.

It is furthermore preferred according to an example embodiment of thepresent invention that the sensor system includes an electrical carrierwhich extends essentially in parallel to the main extension planes ofthe substrates, the individual and separate sensor elements beingmechanically connected to the electrical carrier, in particular theelectrical carrier including electrical strip conductors and/or afurther redistribution level. It is advantageously possible in this waythat the individual semiconductor components of the array (i.e., theindividual sensor elements) are individually addressable via a bussystem, for example via a microcontroller, so that a suitable weightedaveraging of the signals of the individual semiconductor components maybe carried out in the microcontroller. The further redistribution level(on the electrical carrier) is used in particular for electricallyinterconnecting identical pins of the individual semiconductorcomponents (individual sensor elements) and may either take place, forexample, on the carrier element for the flip-chip mounting (for example,a circuit board or a microcontroller ASIC) or may already be implementedby a dedicated metallic redistribution on the array (i.e., as part ofthe above-mentioned redistribution level situated on the side of thesecond substrate facing away from the first substrate (or on the side ofthe first substrate facing away from the second substrate));alternatively, this functionality may also be implemented both via theredistribution level and via the further redistribution level. Inparticular upon use of the redistribution levels (on the outer surfaceof the first or second substrate), the redistribution may also becarried out in such a way that the array may be electrically contactedvia wire bonds; the individual semiconductor components (i.e.,individual sensor elements) within the array are no longer completelyidentical in this case, but rather differ with respect to theirredistribution on the contacting side.

According to an example embodiment of the present invention, it ispreferred in particular that the individual and separate sensor elementsor at least a part of the individual and separate sensor elements areequivalent sensor elements or identical sensor elements (in particularsituated in terms of an array), in particular micro-electromechanicalcomponents (MEMS components), in particular in the form of inertialsensor elements (for example, for measuring the linear acceleration inone, two, or three spatial directions and/or for measuring therotational acceleration or rotation rate, also around axes of rotationin one, two, or three spatial directions) or temperature sensor elementsor pressure sensor elements or actuator elements coming intoconsideration.

With respect to the operation of the sensor system according to thepresent invention, it is preferred according to an example embodiment ofthe present invention that it is configured with respect to theevaluation of the individual and separate sensor elements in such a waythat arithmetic averaging of the measured values of these individual andseparate sensor elements is carried out, and/or weighted averaging ofthe measured values of these individual and separate sensor elements iscarried out. For example, it may be advantageous that at a first pointin time, an arithmetic averaging is carried out and at a second point intime, a weighted averaging of the measured values is carried out.

Exemplary embodiments of the present invention are shown in the figuresand explained in greater detail in the description below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic side view as a sectional illustration of anindividual and separate sensor element of a sensor system according toan example embodiment of the present invention.

FIG. 2 shows a schematic side view as a sectional illustration of thesensor system according to an example embodiment of the presentinvention, implemented for the example of a 1×3 array.

FIG. 3 shows a schematic top view of the electrical carrier or the outerside of the first or second substrate of the sensor system according toan example embodiment of the present invention, implemented for theexample of a 2×3 array, for a first specific embodiment of the presentinvention,

FIG. 4 shows a schematic top view of the electrical carrier or the outerside of the first or second substrate of the sensor system according toan example embodiment of the present invention, implemented for theexample of a 2×3 array, for a second specific embodiment of the presentinvention,

FIG. 5 shows a schematic top view of the outer side of the first orsecond substrate of the sensor system according to an example embodimentof the present invention, implemented for the example of a 2×3 array,for a third specific embodiment of the present invention.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

In the various figures, identical parts are provided with identicalreference numbers and are therefore generally each only named ormentioned once.

A schematic side view is shown as a sectional illustration of anindividual and separate sensor element 100 of a sensor system 200according to the present invention (cf. FIG. 2) in FIG. 1 as anexemplary specific embodiment. FIG. 1 thus shows the basic structure ofan individual sensor element according to the present invention, sensorsystem 200 including a plurality of such sensor elements 100 orindividual sensor elements 100, in particular a plurality of such sensorelements 100 which are constructed similarly or identically. Individualsensor element 100 is implemented in particular as a so-calledASICAP-MEMS component 100, i.e., it includes a first substrate 42 havinga micromechanical sensor structure, formed or implemented in (orprimarily in) a micromechanical functional layer 48, and a secondsubstrate 12 having an associated evaluation circuit 14. Substrates 42,12 include main extension planes which are situated essentially inparallel to one another, first and second substrate 42, 12 beingmechanically and electrically connected to one another (i.e., in the“vertical” direction, i.e., perpendicular to the main extension planes)and first and second substrate 42, 12 overlap in a directionperpendicular to the main extension planes or form an at least partiallysealed cavity, within which in each case the micromechanical sensorstructure or functional layer 48 of individual sensor elements 100 issituated. One such sensor element 100 includes in particular an ASICchip 10 (or second chip arrangement) and a MEMS chip 40 (or first chiparrangement), first and second chip arrangement 40, 10 (or first andsecond substrate 42, 12) being mechanically connected to one another inparticular via a metallic bond connection 30 (and in particularhermetically sealing an enclosed cavity). Bond connection 30 seals offthe chip, in particular hermetically, at outer bond frame 30 andoptionally additionally provides electrical contacts 32. MEMS chip 40 orfirst chip arrangement 40 may be manufactured, for example, usingsurface-micromechanical methods according to the related art andincludes a MEMS wafer substrate 42 (first substrate 42) and (exemplary)oxide layers 44, 46, a silicon redistribution level 45, and amicromechanical functional layer 48. The ASIC or second chip arrangement10 includes an ASIC wafer substrate 12 (second substrate 12) andfunctional layers (not differentiated in greater detail) for transistorsand redistribution, i.e., for implementing the circuit functionality ofthe ASIC. ASIC component 100 or individual sensor element 100furthermore includes vias 16 (or TSVs (through-silicon vias) 16), withthe aid of which first and second substrate 42, 12 (or first and secondchip arrangement 40, 10) are connected to one another and/or first orsecond substrate 42, 12 is electrically connected to an outside of firstor second substrate 42, 12 facing away from the particular othersubstrate (for the first substrate 42 (from its inside facing towardsecond substrate 12) to its outside, which faces away from secondsubstrate 12, or for second substrate 12 (from its inside facing towardfirst substrate 42) to its outside, which faces away from firstsubstrate 42. In this way, it is possible according to the presentinvention in particular to lead ASIC signals to the rear side of theASIC (of second chip arrangement 10) (or vice versa to lead signals ofMEMS chip 40 (of first chip arrangement 40) to its rear side (thislast-mentioned alternative not being shown in FIG. 1). Passivationlayers 18 and a redistribution level (RDL, redistribution layer) 20 arelocated on the rear side of the ASIC or second chip arrangement 10.Solder balls 110 may be situated by a suitable metallization of padareas with the aid of an under-bump metallization (UBM, not shownseparately), which are soldered with the aid of soldering on anelectrical carrier 120 (which is provided with contact pads 130).Electrical carrier 120 is typically a circuit board, but it may also bean interposer or an active semiconductor chip.

FIG. 2 shows a schematic side view as a sectional illustration of sensorsystem 200 according to the present invention, implemented for theexample as a 1×3 array, i.e., of three individual sensor elements 100(or of ASICAP components) situated adjacent to one another. Singleindividual sensor elements 100 (or ASICAP components) may be, forexample, acceleration sensors, rotation rate sensors, pressure sensors,temperature sensors, actuators, in particular micromechanical actuators,or the like. Scribe lines 50 are located between individual sensorelements 100 (or ASICAP components). Except for the substrate potential,individual chips (or individual sensor elements 100) of array 200 (or of(entire) sensor system 200) are therefore only mechanically, but notelectrically, connected to one another. This applies in particularaccording to one specific embodiment without redistribution level 20(which includes or implements electrical connections between multipleindividual sensor elements 100 (or ASICAP components)) as part of secondsubstrate 12. In an alternative specific embodiment with aredistribution level 20 (which is implemented in such a way that itincludes or implements electrical connections between multipleindividual sensor elements 100), this no longer strictly applies;nonetheless even in such a specific embodiment, individual sensorelements 100 are in any case not electrically connected to one another“in the interior” of individual sensor elements 100, i.e., in this casea redistribution level 20 is only situated on the outside of eitherfirst substrate 42 or second substrate 12 (i.e., on the side of secondsubstrate 12 facing away from first substrate 42 or on the side of firstsubstrate 42 facing away from second substrate 12), with the aid ofwhich individual sensor elements 100 (or ASICAP components) areelectrically connected to one another. Scribe line 52 is significantlyreduced in its width by the separation process at the outer edge ofarray 200 or sensor system 200.

The exemplary embodiments of FIGS. 1 and 2 show micromechanicalcomponents, in particular micromechanical components which are formedfrom a vertically integrated wafer stack. This represents a preferredimplementation of the present invention; however, it is not requiredaccording to the present invention that individual and separate sensorelements 100 are micromechanical components, and furthermore, it is alsonot required that individual and separate sensor elements 100 are formedfrom a vertically integrated wafer stack.

It is thus possible according to the present invention that individualand separate sensor elements 100 are semiconductor components, which aresolely formed from a wafer or ASIC wafer substrate 12 and aremanufactured using methods which are conventional in semiconductormanufacturing, for example, the manufacturing of CMOS wafers. Oneexample of this is an integrated temperature sensor as individual andseparate sensor element 100, in which the temperature is sensed via aresistance measurement, the temperature-sensitive resistors, forexample, being formed by doped piezoresistive silicon structures ormetal strip conductors. Individual and separate sensor elements 100 eachcontain an evaluation circuit for reading out the resistors, for signalprocessing and/or communication. In this case, no specialmicromechanical manufacturing methods are required. A separate visualrepresentation is therefore omitted for the sake of simplicity.

Furthermore, it is possible in terms of the present invention thatindividual and separate sensor elements 100 are micromechanicalsemiconductor components, which are not formed from a verticallyintegrated wafer stack, but rather from an individual wafer or ASICwafer substrate 12, to which, however, additional micromechanicalprocess steps are applied. For example, in addition to the process stepsrequired for manufacturing the evaluation circuit, special layerdepositions and/or etching methods for implementing MEMS structures onASIC wafer substrate 12 may be applied in order, for example, to formmovable structures for integrated inertial sensors or diaphragms forintegrated pressure sensors. A separate visual representation is alsoomitted for the sake of simplicity.

FIG. 3 shows a schematic top view of electrical carrier 120 (shown onthe right in FIG. 3) and the outer side of first and second substrate42, 12 of sensor system 200 according to the present invention,implemented for the example as a 2×3 array 200, for a first specificembodiment of the present invention. According to the first specificembodiment, a 3×2 array 200 of individual semiconductor components 100is shown by way of example, each individual component (individual sensorelement 100) including six electrical contacts, for example orpreferably solder balls which periodically repeat themselves withinarray 200, corresponding contacts being identified in each case with theparticular identical numbers from the set {1, 2, 3, 4, 5, 6}. In thiscase, the electrical contacts of the individual semiconductor componentsare not connected to one another within array 200. The electricalsignals are therefore merged on electrical carrier 120, on which anarrangement of solder pads 130 prepared for the flip-chip mounting issituated and furthermore also strip conductors 150 are situated, whicheach connect identical pads (bus lines, substrate potential, supplyvoltage, etc.) to one another. Therefore, in this arrangement, thesignals of individual semiconductor elements (or individual sensorelements 100) of array 200 are merged and possibly further processed onelectrical carrier 120. One advantage of this variant is that allindividual semiconductor chips (or individual sensor elements 100) onarray 200 (or sensor system 200), including the metallic redistribution(in redistribution level 20 of second substrate 12 according to FIG. 1),are identical. As a result, the same wafer type may be separated asneeded without changes of the wiring into arrays (sensor systems 200) ofdifferent sizes, thus, for example, 2×2, 3×3, and 4×4.

FIG. 4 shows a schematic top view of electrical carrier 120 (shown onthe right in FIG. 4) and the outer side of first and second substrate42, 12 of sensor system 200 according to the present invention,implemented for the example as a 2×3 array 200, for a second specificembodiment of the present invention. This second specific embodimentcorresponds to an alternative, according to which it is possible tocarry out a connection of equivalent electrical contacts of individualsemiconductor components (or individual sensor elements 100) already onthe array (or sensor system 200). A corresponding wiring diagram isagain shown in FIG. 4 for a 3×2 array (in this case the six contacts areshown by different types of lines, i.e., dashed, dotted, dot-dash,etc.). Strip conductors 150 connect electrical contacts of variousindividual sensor elements 100 of sensor system 200 here. This variantrequires a dedicated redistribution on array 200, which is specific forthe array dimension (a 2×2 array requires different wiring than, forexample, a 4×4 array). However, the expenditure for this purpose is onlyvery minor in comparison to the total expenditure for manufacturingsemiconductor elements 100. Therefore, the wiring complexity for thispurpose is significantly simplified on electrical carrier 120, since, asshown by way of example in FIG. 4, only six active contact pads 130 arestill required and remaining solder contacts 140 are passive and arethus only used for the mechanical fixation of array 200. Since soldercontacts generally have higher error risks with respect to reliability(for example, breakdown of solder balls due to aging, temperature, harshenvironmental conditions) than redistributions, the reliability orquality may be enhanced by this arrangement in comparison to thearrangement of FIG. 3. Alternatively, to the arrangement of activecontacts 130 of FIG. 4, it is also possible to arrange all the activecontacts in the outermost ball row of array 200, in order to thusfacilitate an automated solder point check during the final assembly ofarray 200.

FIG. 5 shows a schematic top view of the outer side of first and secondsubstrate 42, 12 of the sensor system according to the presentinvention, implemented for the example as a 2×3 array, for a thirdspecific embodiment of the present invention. According to the thirdspecific embodiment, a redistribution is implemented (for example inredistribution level 20 of second substrate 12), by which thepossibility is provided of implementing bond pads 170 for wire bonding.This option may be advantageous for specific applications and housingforms. Risks which are linked to the flip-chip mounting, for example,solder ball disruption and delamination, may thus be avoided. It mayalso be necessary for the function in the case of an array 200 made upof sensors having media access, for example, pressure sensors or gassensors, to dispense with the flip-chip mounting.

The electrical connection of array 200 according to the presentinvention or sensor system 200 according to the present inventionpreferably takes place to a special ASIC or microcontroller (not shown),in which the signal processing is carried out. Various types of signalprocessing are possible, for example, arithmetic averaging, weightedaveraging, a plausibility check, inserting or suppressing signals ofindividual semiconductor components or individual sensor elements 100.Moreover, additional pieces of information may be obtained by datafusion or data analysis from array 200, which individual semiconductorcomponent 100 or individual sensor element 100 cannot supply.

Additional pieces of information which the individual semiconductorcomponent cannot supply are particularly preferably obtained from thedata of array 100. The following examples are listed in this regard:

-   -   in a temperature sensor array 200, for example, reading out        lateral temperature gradients by way of differences in the        measured temperature in the individual temperature sensors;    -   in an acceleration sensor array 200, for example, determining an        axis of rotation by measuring centrifugal accelerations acting        at different strengths on the individual acceleration sensors;    -   in a pressure sensor array 200, for example, determining the        inclination of array 200 by reading out the differences in the        barometric pressure between the individual pressure sensors (a        very high resolution being required for this purpose, however,        because pressure differences have to be resolved which        correspond to height changes in the order of magnitude of 1 mm        and less).

The signal averaging within the array particularly preferably takesplace via arithmetic averaging. However, in specific cases, it may bepreferred to carry out weighted averaging, for example if it turns outthat semiconductor components 100 (or individual sensor elements 100) atthe outer edge or in the corners of a 4×4 array supply greater errors,for example due to bending stress on the circuit board, than thesemiconductor components located farther inward. In this case, it ispreferred that the signals of the semiconductor components locatedfarther inward are incorporated with greater weight in the signalaveraging.

It is also preferred according to the present invention that differentaveraging methods are used within array 200 for different measuredvariables of individual semiconductor components 100. For example, it ispossible in this way that in an acceleration sensor array 200, the noiseis arithmetically averaged (since it is not dependent on the bendingstress, thus the position of the individual sensor in the array), whilethe offset errors, in contrast, are weighted differently (since in thecase of the offset error, the bending stress may act on the offset ofthe individual sensors as a function of the position).

According to the present invention, it is thus advantageously possiblethat an array 200 including multiple semiconductor components 100(individual sensor elements 100) results in improved signal quality(performance) by way of suitable averaging. The improvements relate inparticular to the noise, but also other errors, for example, offset andsensitivity errors of a sensor may be reduced by averaging. Array 200may be scaled very easily, i.e., with little development expenditure,with respect to its performance. For example, if the noise is to bereduced by a factor of 2, the implementation of a 2×2 array fromindividual semiconductor components suggests itself (the noise powerdensity of the overall system decreases for a n×m array at1/(n×m){circumflex over ( )}0.5. If a factor of 4 is required, 4×4arrays may easily be cut out of the wafer or wafer stack (which isidentical except for scribe lines). Because of the low developmentexpenditure, niche applications having increased performancerequirements, for which a separate product development would not becost-effective (due to high development costs at low piece counts), maybe efficiently operated. Due to the preferred implementation as a chipscale package, the dimensions of the array made up of semiconductorcomponents remain in a comprehensible framework which is acceptable formany installation size-sensitive applications. Example: An accelerationsensor may be implemented using present technologies and design conceptsas an individual ASICAP component on an area of approximately 1 mm² witha power noise density of approximately 100 μg/sqrt (Hz). A 4×4 arraymade of such individual acceleration sensors would already reach a noiselevel of approximately 25 μg/sqrt (Hz) at a footprint of 16 mm². Forcomparison: In a construction of correspondingly many conventionalacceleration sensors having a standard footprint of 2×2 mm² andsufficient distance between the individual sensors of, for example, 0.2mm, a total area of approximately 80 mm², thus greater by a factor of 5,would be required. Furthermore, it is advantageously possible accordingto the present invention that due to the redundancy of the signals ofthe individual semiconductor components (individual sensor elements100), these may alternately be checked for plausibility. Function errorsof individual semiconductor components within array 200 may therefore berecognized easily. This aspect may be enormously advantageous forsafety-critical applications, for example, in the automobile (ESPsystems . . . ). Implausible signals may be suppressed by themicrocontroller, and are thus no longer taken into consideration for thesignal averaging.

1-10. (canceled)
 11. A sensor system, comprising: a plurality ofindividual and separate sensor elements, wherein each of the individualsensor elements is independently functional and the individual sensorelements of the sensor system are each formed in one piece from parts ofa wafer or a vertically integrated wafer stack; and at least oneseparation structure between the individual and separate sensorelements.
 12. The sensor system as recited in claim 11, wherein theseparation structure is a scribe line.
 13. The sensor system as recitedin claim 11, wherein the individual and separate sensor elements of thesensor system, with the exception of a connection via a substratepotential, are exclusively mechanically connected to one another or areonly electrically connected to one another via a redistribution level.14. The sensor system as recited in claim 11, wherein each of theindividual sensor elements includes a first substrate having amicromechanical sensor structure and a second substrate having anassociated evaluation circuit, the first and second substrates includingmain extension planes which are situated in parallel to one another, thefirst substrate and the second substrate being mechanically andelectrically connected to one another and the first substrate and thesecond substrate at least partially overlap in a direction perpendicularto the main extension planes or form an at least partially sealed cavitywithin which in each case the micromechanical sensor structure of theindividual sensor elements is situated.
 15. The sensor system as recitedin claim 14, wherein each of the individual and separate sensor elementsincludes a vertically integrated wafer stack made up of a first chiparrangement including the micromechanical sensor structure and the firstsubstrate, and a second chip arrangement including the associatedevaluation circuit and the second substrate.
 16. The sensor system asrecited in claim 15, wherein the first and second substrates and/or thefirst and second chip arrangements are electrically connected to oneanother using vias and/or the first or second substrate are electricallyconnected using vias to an outer side of the first or second substratefacing away from the other substrate.
 17. The sensor system as recitedin claim 11, wherein the sensor system includes an electrical carrier,which extends in parallel to the main extension planes of the first andsecond substrates, the individual and separate sensor elements beingmechanically connected to the electrical carrier.
 18. The sensor systemas recited in claim 17, wherein the electrical carrier includeselectrical strip conductors and/or a further redistribution level. 19.The sensor system as recited in claim 18, wherein the redistributionlevel is situated on a side of the second substrate facing away from thefirst substrate and includes bond pads.
 20. The sensor system as recitedin claim 11, wherein the individual and separate sensor elements areindividually addressable via a bus system.
 21. The sensor system asrecited in claim 11, wherein are least a part of the individual andseparate sensor elements are similar sensor elements.
 22. The sensorsystem as recited in claim 21, wherein the similar sensor elementsinclude inertial sensor elements or temperature sensor elements orpressure sensor elements or actuator elements.
 23. The sensor system asrecited in claim 11, wherein the sensor system is configured, withrespect to an evaluation of the individual and separate sensor elements,in such a way that an arithmetic averaging of measured values of theindividual and separate sensor elements is carried out, and/or that aweighted averaging of the measured values of the individual and separatesensor elements is carried out.